Cheryl Kimball's Nature Talks: Where do chipmunks go in winter?

Columnist Cheryl Kimball's dog, Oliver, has been wondering what happens to all the chipmunks during the winter. (Courtesy/Cheryl Kimball)

Winter is almost two-thirds over. Things are changing. One of the most obvious is longer daylight hours. This alone can help me get through February a little better. As we get closer to March, my mantra when those late snowstorms come and cover welcome bare ground with white is “but the snow won’t last long; it will melt fast.”

Another thing that I feel is starting to change is squirrel activity. Oh, the birdfeeder shenanigans of the gray squirrel have been a constant throughout the winter. I think someone could do a hilarious parody of the Winter Olympics by videotaping the leaps, pretzel twists and dismounts (planned or not) of a gray squirrel and a feeder full of black oil sunflower seed. A so-called “squirrel baffle” seems to baffle them for two minutes at best.

The gray squirrels’ penchant to change their minds, too often to their demise, when crossing the road has been regularly observed all winter — either during the process or after a bad decision. But what I have noticed in the past couple weeks are more red squirrels crossing in front of me on my country road commute.

The difference in the technique with which these two squirrels cross is interesting. The gray squirrel climbs the plowed bank, heads down toward the road, stops to consider long enough for a driver to think it is going to stay put, starts across with its long bushy tail full out behind it, turns back, then decides to go for it all in enough time for the driver to step on the brakes, decide it’s OK, the squirrel is going to stay put, and accelerate just in time for both the car and the squirrel to be in the road at the same time. There is either a “thunk” or there’s not. If there is, I spend the rest of the day feeling horrible while some nearby raven is licking its beak in anticipation of an easy meal. Conversely, the red squirrel appears, makes up its mind, tucks its tail straight up, and makes a mad dash across the road; they are hit much less frequently than their gray squirrel cousins.

The recent reappearance of the red squirrel made me wonder what the difference is in the winter habits of the three rodents we see regularly: the gray squirrel, the red squirrel, and the chipmunk. My little dog Oliver really wants the answer to where the chipmunks go.

The Eastern gray squirrel prepares well for winter. Since, according to the “Peterson Field Guide to Eastern Forests” by John C. Kricher and Gordon Morrison, gray squirrels will not eat white oak acorns after they have sprouted (when there is an increase in the tannins in the acorn, which may or may not be the reason), they tend to eat those immediately as perishables. They store the acorns from red and black oaks. Those they eat — along with about a hundred bucks worth of seed per gray squirrel from your and my bird feeders — over their very active winter.

In the winter it is easy to see the big tangles of leaves in high branches that the squirrels build for nests. Red squirrels also build open nests (called “dreys”) unlike the nocturnal flying squirrels who compete with birds for nest cavity acquisition which, also according to Kricher and Morrison, have typically been excavated by woodpeckers — or the cute big-eyed gliders simply nest in the insulation in our attics. Although active all year long, red squirrels “are less active when the weather conditions are bad and can remain in their dreys for several days at a time” (from the UK website with the remarkable name Red Squirrel Survival Trust).

Why the large gray squirrel does not hibernate like its rodent relative the woodchuck is explained by Kricher and Morrison as simply an evolutionary oversight — the species did not adapt along the way to the requirements of hibernation having never experienced hibernation to be the best means of success for the perpetuation of their species.

But what is the answer to my dog Oliver’s winter-long question, where are those chipmunks that he stalked all through the fall? They are, my friend, way underground in burrows that can be 30 feet long with side chambers and escape hatches (“Peterson First Guide to Mammals of North America” by Peter Alder). Here, explains Kricher and Morrison, they “nearly hibernate but do not quite enter a state of true hibernation.” The chipmunks sleep deeply but awaken on and off throughout the winter — and apparently when they do they don’t stagger far from the burrow.

Cheryl Kimball is a freelance writer who lives north of Rochester. Email her at naturetalksck@gmail.com.